Alburges M E, Huang W, Foltz R L, Moody D E
Department of Pharmacology and Toxicology, University of Utah, Salt Lake City 84112, USA.
J Anal Toxicol. 1996 Oct;20(6):362-8. doi: 10.1093/jat/20.6.362.
Methadone is often invoked for detoxification and maintenance of the opioid addict. We have developed and validated a sensitive and specific method for the analysis of methadone and its metabolites, 2-ethylidene-1,5-dimethyl-3, 3-diphenylpyrrolidine (EDDP) and 2-ethyl-5-methyl-3,3-diphenylpyrroline (EMDP), in human plasma, urine, and liver microsomes. This assay uses a solid-phase extraction. Separation and analysis of the analytes are performed by capillary gas chromatography-positive ion chemical ionization-mass spectrometry. The protonated molecules (MH+) are monitored at m/z 264 and 267 for EMDP-d0 and -d3, m/z 278 and 281 for EDDP-d0 and -d3, and m/z 310 and 313 for methadone-d0 and -d3. The recovery of methadone and its metabolites exceeded 85% in the different matrices analyzed. Linear standard curves in plasma and in urine were obtained over the concentration range of 10-600 ng/mL (coefficients of determination: methadone, > or = 0.995; EMDP, > or = 0.994; and EDDP, > or = 0.996). With plasma and urine fortified at 25, 100, and 300 ng/mL, the assay was precise (intra-assay coefficients of variation [CVs], 2-12%; interassay CVs, 1-15%) and accurate (intra-assay percent of target, 85-107; interassay percent of target, 88-105) for all three analytes. Stability studies indicated that methadone and its metabolites are stable at room temperature in plasma and in urine for at least 1 week and in liver microsomes for at least 24 h. This method has now been shown to be useful for quantitation of methadone, EDDP, and EMDP in human urine and plasma and is also useful for quantitation of the amount of EDDP produced in human liver microsomes incubated with methadone. It provides an accurate and precise analytical tool for further studies on the metabolism of methadone.
美沙酮常用于阿片类成瘾者的脱毒和维持治疗。我们已开发并验证了一种灵敏且特异的方法，用于分析人血浆、尿液及肝微粒体中的美沙酮及其代谢物，即2-亚乙基-1,5-二甲基-3,3-二苯基吡咯烷（EDDP）和2-乙基-5-甲基-3,3-二苯基吡咯啉（EMDP）。该测定采用固相萃取法。分析物的分离和检测通过毛细管气相色谱-正离子化学电离-质谱联用进行。对于EMDP-d0和-d3，监测质子化分子（MH+）的质荷比为m/z 264和267；对于EDDP-d0和-d3，质荷比为m/z 278和281；对于美沙酮-d0和-d3，质荷比为m/z 310和313。在所分析的不同基质中，美沙酮及其代谢物的回收率超过85%。在血浆和尿液中，浓度范围为10 - 600 ng/mL时获得线性标准曲线（测定系数：美沙酮，≥0.995；EMDP，≥0.994；EDDP，≥0.996）。血浆和尿液中添加浓度为25、100和300 ng/mL时，该测定对所有三种分析物均具有精密度（批内变异系数[CVs]，2 - 12%；批间CVs，1 - 15%）和准确度（批内目标百分比，85 - 107；批间目标百分比，88 - 105）。稳定性研究表明，美沙酮及其代谢物在血浆和尿液中室温下至少稳定1周，在肝微粒体中至少稳定24小时。现已证明该方法可用于定量人尿液和血浆中的美沙酮、EDDP和EMDP，也可用于定量与美沙酮一起孵育的人肝微粒体中产生的EDDP量。它为美沙酮代谢的进一步研究提供了一种准确且精密的分析工具。
